"This study has shown that motor skills have an impact on later activity and fitness," says Barnett, who carried out the research as part of her PhD.

Theories suggest that children with good motor skills become more physically active adolescents, but until now no studies have tested this by following children from primary to secondary school.

In their study Barnett and colleagues followed 276 children from age 10 to age 16 in schools in northern New South Wales.

They compared what happened to groups of children who developed different skills at the age of 10.

One group developed proficiency at hopping, side galloping and vertical jumping - so-called movement skills. Another group developed proficiency at kicking, catching and throwing a ball - labelled "object control" skills.

Barnett found that 10-year-olds who were good at object control skills were more fit when they reached age 16, than those who were not as good.

These children did more sports that require these skills, as well as other activities such as swimming, aerobics, dancing, bike-riding and skateboarding.

"The kids that had better [object control] skills when they were younger were more likely to participate in any sort of activity as adolescents," says Barnett.

Developing proficiency at movement skills (hopping, side-galloping and vertical jumping) at the age of 10 did not lead to more active 16-year-olds, the researchers found.

The study also found the 16-year-olds who were good at object control skills at the age of 10 believed they were better at sports and physical activities than others who weren't.

Barnett thinks being good at manipulating a ball, or some other object, gives children a better self image when it comes to sport and this makes them more likely to be active people.

"Their skill level at 10 helped to determine how they felt about their own physical competence at 16," says Barnett.

Implication for obesity prevention

Current recommendations state that school-age children should participate in 60 minutes or more of moderate-to-vigrous physical activity each day, say the Barnett and colleagues.

But in 2004, 40% of girls and 22% of boys aged around 15-16 did not meet these recommendations.

Barnett says this study shows it's important that attempts to prevent obesity don't focus on general physical activity at the expense of learning specific motor skills.

"You don't want to drop the skill component just to keep them active," she says. "It's not enough to say let's all run round the oval for our physical education."

Barnett says it's also important that those teaching physical education are competent at teaching motor skills.

"If you're a teacher and you don't feel confident in kicking or throwing yourself, you may not be able to teach children," she says.